Draft-gear.



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d'pMES CARDW'ELL, 0F CHCAG-O, XLLINS, ASSIGNOR T0 UNXGN ERAIT WEAR COMJPLNY, 0F CHIGGG, ILLIENOIS, GEGBVATIGN OF ILINXS.

v y c ERAFT-GER.

pecification of Letters Patent.

Application tiled august 23, 1909. Serial lilo, 514,172.

To dll whom it may concern A Be it known that l, JAMEs R. Cennwrtn, citizfen 'of the United States, residing at Ghiaagc, in the county of Cook 'and State of illinois, have invented a certain new and useful improvementV in Draft-Gear, vof which the following is a full, clear, concisc, and,v exact description, reference being had to the accompanying drawings, forming a 1c part of this specification.

"'iy'invention relates to friction draft gear employed in railway service, and has for its object the provision of a construction Whereby a part of the friction-producing mecha- '15 nism is' brought into operation on light pulling and pushing strains, or during initial parts of heavy pulling and pushing strains, additional fr1ct1onproduc1ng elements being brought into operation when the pulling and pushing strains have been sufficiently nr creased. By means of my invention, lighter pulling and pushing strains will be resisted by the lighter friction and heavier pulling and pushing strains will be resisted by the heavier friction.

ln the preferred embodiment of my invention, I use the type of draft gearvdisclosed in my Patents 819,266, dated May l, 1906, and 861,6' 6, dated July 30, 1907, but I do 80 not wish be limited to the type of draft gear shown in my said patents.

My invention will be Well understood by a descriptibn of the preferred enilmdinient thereof, shown in the accompanying draw- Figure l illustrates my improved draft gear in pertpective, certain parts of the structure being broken away and other parts being shown in section, in order that certain 40 details of construction may be revealed.

Fig. 2 is a view in elevation of a two-part centrally disposed friction-producing elenient preferabiy entering into my improved construction. Fig. 3 is a plan view of a modification of the central friction member.

Like parts are indicated by similar characters of reference in both figures. The center sills a may be of any wellknown or suitable construction. rlhe yoke a is attached to the shank 0 of the coupler bar.

with correspondingly inclined surfaces pro-- designed to travel transversely of the sills.

The portions of the members g and it upon which the friction surfaces that engage with the blocks Q q are provided, are preferably in the form of triangular blocks g1 tl that are loose. with respect to the balance of the members g and )i andwith respect to each other. l speak of the blocks g1 tl as being portions of the members g and h, since the vsaid blocks may remain in position in the absence of the laterally and ,longitudinally acting friction members, andas the invention is not to be limited to these movable blocks. These triangularblocks being loore, the particular elements of the members g and that carry the same are provided with pockets g2 h2, into which the said triangular blocks are received. There are two triangular blocks for each element g and it, as indicated, which are associated with a supple- ,mental friction-producing member divided transversely into two parts g1 for the purpose to be stated, and which is provided with inclined friction surfaces at its ends that are adapted to engage adjacent friction surfaces upon each set of triangular frictionl blocks, these latter' friction surfaces diverging away from the central longitudinal line of the The friction blocks or members y g are provided with apertures extending transversely of the sills through the blocks, through which apertures the bolt ff' is passed, which bolt is surrounded with coil-springs s s that engage at their inner ends castings t, that are desirably separately formed With respect to the blocks g g for utility and convenience is assemblage and construction, the castings t or block mechanism passing through holes in the sills into engagement with the blocks g g'. The outer ends of the bolt fr are provide-'il with caps u 'at that are preferably adjustable, whereby the tension of the springs s between said caps and the castings t maybe regulated. The springs s s, acting through the castings t upon the blocks g, normally bring the said blocks in aroxirnity and effect separation of the inenr bers g and fz.. 7When the member 7a is moved forward upon a sufficient pull upon the shank of 'the coupler and when the member g is moved rearwardly upon a sufficient push upon the shankof the coupler, the blocks g are nfoyedapat'against the force 'ofy the springs 's s',`whi'ch are proportioned to offer positions when strain upon the shank of the coupler has been removed.

f'W-heniasnflciently great pulling or pushf ing strain is eXerted,the triangular friction blocks g1 h1 first are effective to thrust the transversely 'movable friction blocks g ,apartl Vagainst the forcenof the spring devices '8., ,the Afriction then produced being vlimited to the outer faces of the triangular blocks and the inner sloping faces of the transversely, movable blocks q. During the time ,thaty the productiony of friction is limited vto these four places of Contact., the

blocks Iglare moved toward each Aotherand 4then are virtually one with the associate triangular blocks, during which time also it is very apparent thatv the triangular friction blocks of each set Aare not spread apart,

so that no friction occurs between the end faces' of the triangular frictionblocks and the vertical end faces of the poclreted follower-plates g k. However, when the inner ends of the blocks g1 are brought into contact, these blocks q1 will, upon continued appr'oaehof the two sets of triangular blocks, wedge the blocks of each set apart, so that there will be increased vfriction due to the slidingof the vertical end faces of the trian gular blocks upon the vertical end walls of the pocketed follower-plates g and h, and further friction will result as a consequence of the sliding engagement of the blocks g1 with the inner inclined faces of the triangular blocks. ciently light pulling and pushing strains, or fn the case of the initial parts of heavierl pushing andpulling strains, there are four places where friction is being produced, whereas on Ithe heavier pulling and pushing strains, there are twelve places where'friction is being produced. In this way lighter friction is produced where lighter' friction only is required, and much ,increased fric-v tion is produced where much heavier friction is required.- Moreover, it will be apparent that the opposition o'll'ered by the spring devices s s is less during the time thebloeks y1 are out of contact than is the4 case when said blocks (/1 are'brought together, less opposition being vneeded from the spring devices on the lighter pulling and pushing strains and more opposition being needed from the spring devices f during heavier pulling and pushing strains.

In Fig. 3 there is shown a modification of the structure in which the element-s (1101,

interengage, one thereof being formed with a tenon (/2 and the other with a c01nplementary mortise (f. By this arrangement Thus in the case of suili!v ffollowers g h. i 4 y i* H'I have-'herein shown and particularly de- .scribed .the advantages that 'result' from my invention when such invention is embodied in the type of draft gear illustrated inthedrawing, but I do'not -.wish5ftofbe limited in all embodiments of; my inven-, tion to the adaptation thereof :to the precise form of draft gear shown.y

Having thus described my invention,l I, Y

claim as new and desire to .secure'by Letters f 1. -A friction` draft gearincluding relatively movable triangular 'fric'tionblocks, a central longitudinally disposed friction element g1 interposed betweenv and frictionally engaging the same, and transversely lmov`` able friction blocks g between which ,the

said-i friction element g1 isdisposed, which l blocks g also'have frictionaly engagen'fent with the triangular blocks, thefrictioneroducing element-.J g1 being divided transverselyjginto 'two parts, and adapted. to occupy a separated relation when the friction blocks g; 'are closest together and? being adapted-for Contact upon a predetermined separationof the friction 'blocks g.

y2. In ladraft gear, in combination, aupair of followers, a pair of alined wedge-blocks .f

located on the median line ofthe path '.of the followers; the combined length of such blocks 4determining the limit of the rela 4tively approaching movement'of the follow ers; a pair of. opposed laterally movable wedging members engaging the 'wedgeblocks, and springs urging the wedging elements inward.

3. In -a draft gear,in combination,`a pair of opposed followers, a pair of wedge-blocks seated against the inner face of each follower, a pair of laterally movable wedgeblocks each engaging the outer lateral faces of one member of each pair of the first-mentioned wedge-blocks, means for yieldingly urging the second-named wedge-blocks inwardly, and a second pair of wedge-blocks respectively engaging the inner faces of the members of the-two pairs of Wedge-blocks.

first-named, the inner ends of the central wedge-blocks being normally out olf-conhaving oppositely disposed wedging faces.Il

a laterally extending rod, oppositely disposed wedge-shapcd friction shoes slidably i mounted thereon, spripgs pressing the shoes' 1 als inwardly, and limiting stops on each wedge adapted to Contact each other, substantially as specified.

5. In a draft rigging, 1n combination; a

. yoke; center sills; stops; followers; wedges; friction shoesmovable transversely of said sills and cooperating with the wedges; springs copereting with said shoes; and a projeotionon one of the wedges extending toward the opposite wedge and adapted to engage the latter when the followers are compression of the moved relatively toward each other, to thereby limit the amount of movement and springs, substantially as specified.`

vIn witness whereof, I hereunto subscribe my name this twenty-lirst dey of August A. D.,v 1909.

l JAMES R. CARDWELL. Witnesses:

G. L. CRoGG, L. G. STROH. 

